The present invention relates to an ink sheet cartridge, and to an exchangeable ink sheet set which can be attached to the ink sheet cartridge.
In general, a thermal printer employs an ink ribbon cartridge which eases replacement of an ink ribbon, i.e., handling of the thermal printer. When the thermal printer is configured as a line printer, a wide ink sheet is used.
Japanese Patent Provisional Publication No. 2001-277627 discloses an ink sheet cartridge having the wide ink sheet. The ink sheet cartridge disclosed in this publication includes a supply core tube, a takeup core tube, and a cartridge body. Spools are attached to both ends of the supply core tube and the takeup core tube so that each of the core tubes is rotatably attached via the spools to right and left side walls of the cartridge body.
In the ink sheet cartridge, an intermediate connector is interposed between one of the spools and an end portion of the supply core tube. FIG. 18 schematically shows the intermediate connector 103 and one of the supply core tube 101 as a front view. As shown in FIG. 18, the intermediate connector 103 has a resilient pawl 104 which engages with a mating groove 102 formed at the end portion of the core tube 101. The resilient pawl 104 has an arm portion 104a and a pawl portion 104b. 
The resilient pawl 104 has a form of a letter “L” and extends from a maximum diameter portion 103a of the intermediate connector 103 in an axial direction of the core tube 101. When the intermediate connector 103 is inserted into the end portion of the core tube 101, the resilient pawl 104 is also inserted into the mating groove 102. Then, the resilient pawl 104 engages with the mating groove 102.
The above mentioned configuration shown in FIG. 18 requires the intermediate connector 103 to connect the spool (not shown) to the core tube 101. Therefore, the configuration prevents a non-regular ink sheet (e.g., one provided by a non-regular vendor which is different from a regular vendor of the ink sheet cartridge having the configuration shown in FIG. 18) from being erroneously attached to the cartridge body (not shown in FIG. 18).